Serious Adverse Events Following Immunization During Polio Outbreak Response in Ethiopia, January 2024–July 2025
- Presentation Day/Time: Friday, April 24, 9:45 AM
- Presenter: Hailey Whitmire, PharmD, MPH, MBA, Global Health Center, Global Immunization Division
The Issue
- In December 2024, the Ethiopian Food and Drug Authority (EFDA) received reports of eight serious adverse events following immunization (AEFIs) after combined novel oral polio vaccine type 2 (nOPV2) and routine childhood vaccine campaigns that reached 5.8 million children.
What We Did
- We reviewed serious AEFIs reported in children under 18 years of age reported to EFDA during January 2024–July 2025, examined their frequency, distribution, and clinical presentations, and calculated annualized incidence rates following nOPV2 for comparison with global estimates. Additionally, we reviewed data management processes and observed ongoing AEFI investigations and causality assessments to evaluate surveillance system performance.
What We Found
- Among 122 persons with reported serious AEFIs, 226 vaccine doses were received, including 40 (18%) nOPV2 among 40 persons. Serious AEFIs following nOPV2 most frequently involved gastrointestinal illness (20%), fever (10%), and paralysis (10%).
What This Means
- Available evidence indicates no safety signals for nOPV2 in Ethiopia, with observed serious AEFI rates below global estimates. The AEFI surveillance system was strengthened to support improved reporting, detection, and investigation.
